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How to sum up an array of integers in C#
...is worth noting that this will get raise an error System.OverflowException if the result would be greater than you can fit in a signed 32 bit integer (i.e. (2^31) -1 or in english ~ 2.1 billion).
– ChrisProsser
Mar 14 '15 at 20:15
...
Counting DISTINCT over multiple columns
...
If you are trying to improve performance, you could try creating a persisted computed column on either a hash or concatenated value of the two columns.
Once it is persisted, provided the column is deterministic and you are ...
RegEx: Grabbing values between quotation marks
...explanation from user ephemient:
([""']) match a quote; ((?=(\\?))\2.) if backslash exists, gobble it, and whether or not that happens, match a character; *? match many times (non-greedily, as to not eat the closing quote); \1 match the same quote that was use for opening.
...
Access lapply index names inside FUN
... will pass in the "element" (here the index) to the first argument not specified among the extra ones. In this case, I specify y and n, so there's only i left...
Which produces the following:
[[1]]
[1] "a 11"
[[2]]
[1] "b 12"
[[3]]
[1] "c 13"
UPDATE Simpler example, same result:
lapply(seq_al...
Can we pass parameters to a view in SQL?
...
What are the practical differences between this and a view? Can you assign user permissions to only access this function?
– MikeMurko
Oct 22 '12 at 17:44
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What file uses .md extension and how should I edit them?
...tensions .md and .markdown are just text files written in Markdown syntax. If you have a Readme.md in your repo, GitHub will show the contents on the home page of your repo. Read the documentation:
Standard Markdown
GitHub Flavored Markdown
You can edit the Readme.md file in GitHub itself. Click...
Difference between onCreateView and onViewCreated in Fragment
What's the essential difference between these two methods? When I create a TextView, should I use one over the other for performance?
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Why does C# not provide the C++ style 'friend' keyword? [closed]
...ut the internal classes and their use you should be fine.
EDIT Let me clarify how the friend keyword undermines OOP.
Private and protected variables and methods are perhaps one of the most important part of OOP. The idea that objects can hold data or logic that only they can use allows you to writ...
Passing a method as a parameter in Ruby
... off the method.
def weightedknn(data, vec1, k = 5)
...
weight =
if block_given?
yield(dist)
else
gaussian.call(dist)
end
end
...
end
weightedknn(foo, bar) do |dist|
# square the dist
dist * dist
end
But it sounds like you would like more reusable chunks of c...
Best way of invoking getter by reflection
I need to get the value of a field with a specific annotation, So with reflection I am able to get this Field Object. The problem is that this field will be always private though I know in advance it will always have a getter method. I know that I can use setAccesible(true) and get its value (when t...